A substance in which the valence and conduction bands overlap is (a) a semiconductor; (b) a metalloid; (c) a metal; (d) an insulator.

Short Answer

Expert verified
The correct answer is (c) a metal.

Step by step solution

01

Understand the Electronic Band Structure

In solid-state physics, the electronic band structure of a solid describes the range of energies that an electron within the solid may have (called energy bands, allowed bands, or simply bands) and ranges of energy that it may not have (called band gaps or forbidden bands). The term 'band' originates from the characteristic energy band structure that arises from the behavior of electrons in solids as a consequence of the indistinguishable nature of particles. The band structure of a solid determines its properties as an insulator, metal, or semiconductor.
02

Distinguish Between the Different Materials

Semiconductors, metalloids, and insulators have a band gap between the valence band and the conduction band. In metals, however, the valence and conduction bands overlap, allowing free movement of electrons. Therefore, metals can conduct electricity.
03

Answer the Question

Based on the above distinction, it is clear that the substance in which the valence and conduction bands overlap is a metal.

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Most popular questions from this chapter

Explain why the molecular structure of \(\mathrm{BF}_{3}\) cannot be adequately described through overlaps involving pure \(s\) and \(p\) orbitals.

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